1. Field of the Invention
The present invention relates generally to preparing blood vessels for a vascular anastomosis procedure and more particularly to a system and method for forming and holding precise incisions in a target vessel.
2. Description of Related Art
Vascular anastomosis is a procedure where two separate blood vessels of a patient are surgically grafted together. The vascular anastomosis procedure is routinely performed during the treatment of a variety of conditions, including coronary artery disease, diseases of the great and peripheral vessels, organ transplantation and other types of trauma. When a patient suffers from coronary artery disease (CAD), an occlusion or stenosis in a coronary artery restricts blood flow to the heart muscle. In order to treat CAD, the area where the occlusion occurs is bypassed. The area is bypassed through rerouting blood flow by grafting a vessel in the form of either a prosthesis, a harvested artery or a vein. When the vessel is grafted to bypass the blocked coronary artery, the occlusion is avoided and adequate blood flow is restored to the heart muscle. This treatment is known as coronary artery bypass grafting (CABG).
When a CABG is performed, a large incision is made in the chest of a patient and the sternum is separated in order to allow access to the heart of the patient. Moreover, the patient is connected to a heart lung machine which circulates the blood of the patient. After the heart lung machine is connected to the patient, the patient's heart is stopped in order to perform the vascular anastomosis. However, stopping the patient's heart is very traumatic to the patient.
In order to minimize the trauma to the patient induced by the CABG, less invasive techniques have been used. These less invasive techniques include performing a series of small incisions in the patient's chest. Once the incisions are completed, surgery is performed with the aid of visualizing scopes. The less invasive techniques may be performed on a beating heart in order minimize trauma to the patient, thereby avoiding the need for cardiopulmonary bypass.
In both the conventional and less invasive CABG techniques, a surgeon makes an incision in a coronary artery in order to allow grafting of a graft vessel to the coronary artery. However, as the surgeon makes an incision in the coronary artery, an incision without a definable geometry results, as shown with respect to FIG. 1. FIG. 1 is a schematic of a top view of a coronary artery 102 after the formation of an incision by a surgeon in accordance with the prior art. During both the conventional and less invasive CABG techniques, a surgeon forms an incision 104 in the coronary artery 102 as shown with respect to FIG. 1. As those skilled in the art will appreciate, the incision 104 includes walls 104a and 104b which do not define a geometry. The imprecise geometry of the incision 104, as illustrated by the walls 104a and 104b, make grafting a graft vessel to the coronary artery 102 difficult.
In addition, as may be seen with respect to FIG. 1, the incision 104 is not held in place. Instead, the geometry of the incision 104 is dictated by the orientation of the coronary artery 102. To further illustrate, if the coronary artery 102 shifts during an anastomotic procedure, the geometry of the incision 104 changes, thereby making grafting even more difficult. As a result, suturing a graft vessel to the coronary artery requires a greater amount of time and surgical skill, thereby increasing the overall cost to perform an anastomotic procedure.
Furthermore, once the surgeon makes the incision 104 in the coronary artery 102, the surgeon must suture a graft vessel to the coronary artery 102. Typically, the surgeon sutures the graft vessel to the coronary artery by hand sewing the vessel using a needle the size of an eyelash. As may be appreciated, this technique requires a great amount of skill on the part of the surgeon and a great amount of time. Thus, both the time and financial costs are greatly increased for the patient. In addition, during both the conventional techniques and the less-invasive techniques, the possibility of trauma to the patient is further increased due to the greater amount of time required to perform the surgery.
In addition to suturing, other methods used during an anastomosis to graft a graft vessel to a coronary artery involves the use of an automated anastomosis instrument. However, when an automated anastomosis instrument is used, accurate location of the tissue is important to achieve accurate and leak-proof grafting.
Accordingly, a need exists for a method to form and hold incisions having a definable geometry in order to allow precise grafting of a graft vessel to a target vessel. This new method should minimize the time associated with grafting a graft vessel to a target vessel, thereby decreasing the possibility of trauma to a patient resulting from a long anastomotic procedure. Also, the new method should minimize the time associated with grafting a graft vessel to a target vessel by providing both a method allowing precise incisions in a target vessel and a simplified method for attaching the graft vessel to the target vessel once the incision is made.